Four hours before the Police bade their final farewell to Britain, a karaoke contestant called Steve was belting out Message in a Bottle in a tent a few hundred feet from Hard Rock Calling's main stage. A middle-aged man in a Stranglers T-shirt, Steve had a gritty voice for a Sting stand-in, but still he managed what none of the afternoon's paid acts could - he got a crowd going crazy.

The daytime bill was positively dreary. Starsailor struggled to convince that a comeback could be on the cards, while KT Tunstall's folk-pop felt lacklustre. The best bet was to stick with Steve, who was no doubt down the front at the Stranglers' surprisingly good soiree. A superb Skin Deep, a truly spooky Strange Little Girl and a gorgeous Golden Brown proved that some successful rock reunions aren't about making millions.

Since Sting swallowed his pride to re-form the Police 16 months ago, he has coined enough to buy a small country. He has also discovered a genuine respect for his former friends. There was no trace of the tension between the trio earlier in the tour. Nor, thankfully, of the jazzy interludes previously imposed to remind the band who is boss. Looking lean in casual black clothes, with grey peppering a spiky beard and a smile on his face, Sting proved the perfect party host. “London, are you ready to sing?” he asked three times, after introducing “the legendary Andy Summers” and “the extraordinary Stewart Copeland” midway through the opener, Message in a Bottle. Favourites came thick and fast: Don't Stand So Close to Me, Walking on the Moon and When the World is Running Down in particular had gone decades without dating.

At times the crowd was surprisingly subdued; Demolition Man borrowed from the Police's punk days, but was met with polite toe-tapping instead of pogoing. Still Sting kept his cool. “C'mon you posh people over there, put your hands up,” he ordered. Summers sneaked a guitar solo into Every Little Thing She Does is Magic that actually enhanced the song, and even De Doo Doo Doo, De Da Da Da was more ska classic than silly ditty.

An encore that included a stripped-down Roxanne, a grungey King of Pain and a lengthy So Lonely was unforgettably good. Just as they did the first time around, the Police are going out on a high.

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